✨ feat(sql-editor): 关闭应用时提示保存未保存SQL

- 关闭应用前拦截 Wails 退出事件，前端弹出确认退出、保存退出和取消三按钮\n- 保存退出支持外部 SQL 文件和已保存查询，未命名临时查询保留草稿恢复语义\n- 补充退出保护后端测试、前端保存目标测试和多语言文案

internal/app/app.go

@@ -79,26 +79,29 @@ type managedSQLTransaction struct {
 
 // App struct
 type App struct {
-	ctx                context.Context
-	startedAt          time.Time
-	dbCache            map[string]cachedDatabase // Cache for DB connections
-	connectFailures    map[string]cachedConnectFailure
-	mu                 sync.RWMutex // Mutex for cache access
-	updateMu           sync.Mutex
-	updateState        updateState
-	i18nMu             sync.RWMutex
-	localizer          *i18n.Localizer
-	queryMu            sync.RWMutex
-	configDir          string
-	secretStore        secretstore.SecretStore
-	runningQueries     map[string]queryContext // queryID -> cancelFunc and start time
-	sqlTransactionMu   sync.Mutex
-	sqlTransactions    map[string]*managedSQLTransaction
-	jvmPreviewTokenMu  sync.Mutex
-	jvmPreviewTokens   map[string]jvmPreviewConfirmationToken
-	jvmPreviewTokenTTL time.Duration
-	keepAliveCancel    context.CancelFunc
-	keepAliveDone      chan struct{}
+	ctx                           context.Context
+	startedAt                     time.Time
+	dbCache                       map[string]cachedDatabase // Cache for DB connections
+	connectFailures               map[string]cachedConnectFailure
+	mu                            sync.RWMutex // Mutex for cache access
+	updateMu                      sync.Mutex
+	updateState                   updateState
+	i18nMu                        sync.RWMutex
+	localizer                     *i18n.Localizer
+	applicationQuitMu             sync.Mutex
+	allowApplicationQuit          bool
+	applicationQuitPromptInFlight bool
+	queryMu                       sync.RWMutex
+	configDir                     string
+	secretStore                   secretstore.SecretStore
+	runningQueries                map[string]queryContext // queryID -> cancelFunc and start time
+	sqlTransactionMu              sync.Mutex
+	sqlTransactions               map[string]*managedSQLTransaction
+	jvmPreviewTokenMu             sync.Mutex
+	jvmPreviewTokens              map[string]jvmPreviewConfirmationToken
+	jvmPreviewTokenTTL            time.Duration
+	keepAliveCancel               context.CancelFunc
+	keepAliveDone                 chan struct{}
 }
 
 // NewApp creates a new App application struct

internal/app/application_quit.go

@@ -0,0 +1,80 @@
+package app
+
+import (
+	"context"
+
+	"GoNavi-Wails/internal/connection"
+	wailsRuntime "github.com/wailsapp/wails/v2/pkg/runtime"
+)
+
+const applicationBeforeCloseRequestEvent = "app:before-close-request"
+
+var (
+	emitApplicationBeforeCloseRequest = wailsRuntime.EventsEmit
+	quitApplicationRuntime            = wailsRuntime.Quit
+)
+
+// NewBeforeCloseHandler exposes the Wails close guard without binding the
+// lifecycle callback itself as a frontend RPC method.
+func NewBeforeCloseHandler(a *App) func(context.Context) bool {
+	return func(ctx context.Context) bool {
+		if a == nil {
+			return false
+		}
+		return a.beforeClose(ctx)
+	}
+}
+
+func (a *App) beforeClose(ctx context.Context) bool {
+	a.applicationQuitMu.Lock()
+	if a.allowApplicationQuit {
+		a.allowApplicationQuit = false
+		a.applicationQuitPromptInFlight = false
+		a.applicationQuitMu.Unlock()
+		return false
+	}
+	if a.applicationQuitPromptInFlight {
+		a.applicationQuitMu.Unlock()
+		return true
+	}
+	a.applicationQuitPromptInFlight = true
+	a.applicationQuitMu.Unlock()
+
+	emitCtx := ctx
+	if emitCtx == nil {
+		emitCtx = a.ctx
+	}
+	if emitCtx != nil {
+		emitApplicationBeforeCloseRequest(emitCtx, applicationBeforeCloseRequestEvent)
+	}
+	return true
+}
+
+// CancelApplicationQuit resets a previously intercepted close request after
+// the frontend dialog is cancelled or cannot complete a save.
+func (a *App) CancelApplicationQuit() connection.QueryResult {
+	if a == nil {
+		return connection.QueryResult{Success: false, Message: "application is not initialized"}
+	}
+	a.applicationQuitMu.Lock()
+	a.applicationQuitPromptInFlight = false
+	a.allowApplicationQuit = false
+	a.applicationQuitMu.Unlock()
+	return connection.QueryResult{Success: true}
+}
+
+// ForceQuitApplication is called only after the frontend has confirmed that
+// discarding or saving pending SQL edits is acceptable.
+func (a *App) ForceQuitApplication() connection.QueryResult {
+	if a == nil {
+		return connection.QueryResult{Success: false, Message: "application is not initialized"}
+	}
+	a.applicationQuitMu.Lock()
+	a.allowApplicationQuit = true
+	a.applicationQuitPromptInFlight = false
+	a.applicationQuitMu.Unlock()
+	if a.ctx != nil {
+		quitApplicationRuntime(a.ctx)
+	}
+	return connection.QueryResult{Success: true}
+}

internal/app/application_quit_test.go

@@ -0,0 +1,75 @@
+package app
+
+import (
+	"context"
+	"testing"
+)
+
+func TestApplicationBeforeCloseEmitsPromptOnceUntilCancelled(t *testing.T) {
+	originalEmit := emitApplicationBeforeCloseRequest
+	originalQuit := quitApplicationRuntime
+	t.Cleanup(func() {
+		emitApplicationBeforeCloseRequest = originalEmit
+		quitApplicationRuntime = originalQuit
+	})
+
+	var emitted []string
+	emitApplicationBeforeCloseRequest = func(_ context.Context, eventName string, _ ...interface{}) {
+		emitted = append(emitted, eventName)
+	}
+	quitApplicationRuntime = func(context.Context) {}
+
+	app := NewAppWithSecretStore(nil)
+	handler := NewBeforeCloseHandler(app)
+
+	if prevent := handler(context.Background()); !prevent {
+		t.Fatal("expected first close request to be prevented")
+	}
+	if len(emitted) != 1 || emitted[0] != applicationBeforeCloseRequestEvent {
+		t.Fatalf("expected one before-close event, got %#v", emitted)
+	}
+	if prevent := handler(context.Background()); !prevent {
+		t.Fatal("expected repeated close request to stay prevented while prompt is open")
+	}
+	if len(emitted) != 1 {
+		t.Fatalf("expected no duplicate prompt event, got %#v", emitted)
+	}
+
+	result := app.CancelApplicationQuit()
+	if !result.Success {
+		t.Fatalf("expected cancel quit success, got %#v", result)
+	}
+	if prevent := handler(context.Background()); !prevent {
+		t.Fatal("expected close request after cancellation to be prevented again")
+	}
+	if len(emitted) != 2 {
+		t.Fatalf("expected prompt event after cancellation, got %#v", emitted)
+	}
+}
+
+func TestForceQuitApplicationAllowsNextCloseRequest(t *testing.T) {
+	originalEmit := emitApplicationBeforeCloseRequest
+	originalQuit := quitApplicationRuntime
+	t.Cleanup(func() {
+		emitApplicationBeforeCloseRequest = originalEmit
+		quitApplicationRuntime = originalQuit
+	})
+
+	emitApplicationBeforeCloseRequest = func(context.Context, string, ...interface{}) {}
+	quitCalls := 0
+	quitApplicationRuntime = func(context.Context) {
+		quitCalls++
+	}
+
+	app := NewAppWithSecretStore(nil)
+	app.ctx = context.Background()
+	if result := app.ForceQuitApplication(); !result.Success {
+		t.Fatalf("expected force quit success, got %#v", result)
+	}
+	if quitCalls != 1 {
+		t.Fatalf("expected runtime Quit to be called once, got %d", quitCalls)
+	}
+	if prevent := NewBeforeCloseHandler(app)(context.Background()); prevent {
+		t.Fatal("expected next close request to be allowed after force quit")
+	}
+}